Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Topic: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK) (Read 3024 times) previous topic - next topic

Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

April 09, 2013, 12:58:40 am

Quote from: Karl Brenneman – April 05, 2013, 09:49:42 pm

I have a new problem, I have been chasing a air leak for months. Spending countless hours on my back under the MH. with no leak detected. The compressor would go on about every 4 to 5 hours. Today I found something different. Yesterday I raised the coach all the way up so I could work under it. After I was done I did not lower the coach to travel mode, I did press the auto level button which it did level. It has not lost air pressure for 24 hrs. Should I be looking for a leaky check valve and which one.
Any suggestions Thank You Karl

I have been dealing with the same intermittent air leak for some time.
I installed several ball valves to isolate the leaking line.
After closing the ball valve to line 50 to the front manifold the leak stopped.
I cleaned the 6 pack solenoids and replaced the "O" rings.
Sprayed everything for leaks with no luck.

My air line diagram was not matching up to reality so I went back to Colton Truck to get some help on tracing every line so I could have a correct diagram.
I spent another day under the coach with the tech tracing every line and updating my diagram to the new info.

We air pressure tested every line on the front manifold and they all tested good.
Tested all the way to the check valve on the air tank which was previously replaced and assuming it was good.
Found it was leaking. I reminded them that it was replaced by them recently.

They took it apart and found contamination in it.
A white powder, as we dug deeper we found the powder in the wet tank, front and rear tank, as we blew out the air line to the Retarder accumulator to determine which line it was on the diagram it was coming out there to.
Removed the air dryer which was good but found some powder in there also.
It appears the white powder was caused by the desiccant in the previous dryer disintegrating and was passing through the system as a white powder.

As i looked back on my records I remember replacing the air dryer one time that was way over do because I had overlooked it somehow.
It was a mess when they replaced it but I had no idea what had already happened to the lines.
So the powder was intermittently causing the check valve to leak which was giving me erroneous info.

I had seen the powder inside all the check valves which is why I replaced them but having no idea what it was and just chocked it up to moisture caused by the aux compressor coming o so much.
I also replaced the protection valve as it looked pretty corroded with that powder also.
At this point I don't think there is much I can do about it and will probably be facing these intermittent leaks in the future.

The tech mentioned there really is no good way to get it all out. I can try to blow out each and every line but no way to get it all out.

I don't remember reading on the forum anything like this so let me be the first to say watch your air dryer and replace it on time.

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #1 – April 09, 2013, 11:51:19 am

Quote from: Barry Beam – April 09, 2013, 12:58:40 am

I had seen the powder inside all the check valves which is why I replaced them but having no idea what it was and just chocked it up to moisture caused by the aux compressor coming o so much.
I also replaced the protection valve as it looked pretty corroded with that powder also.
At this point I don't think there is much I can do about it and will probably be facing these intermittent leaks in the future.

The tech mentioned there really is no good way to get it all out. I can try to blow out each and every line but no way to get it all out.
I don't remember reading on the forum anything like this so let me be the first to say watch your air dryer and replace it on time.

Ugh! Russell had posted some good photos a few years back after having his air dryer powder "migrate" (and given me nag-munition to keep on top of ours

) Pure Air Plus Air Dryer - An Ounce of Prevention...

Good discussion about the new DA33200 replacement (if you go remanufactured/replacement rather than a rebuild kit) in this thread Haldex air dryer isolation valve with some really good history from BJ.

-M

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #2 – April 09, 2013, 10:39:28 pm

Barry, I wrote some time ago about the white powder (clay I think) and warned...change the desiccant filter regularly, watch this system for its failure causes list of misery.

To review: the prior owner did not change timely is my interpretation. In any case, leveling was not maintained and raise function on front had some problems as well. You could see white material vent when I would test the drain on the four tanks. I got Haldex to suggest solutions, which I reported...so if this new to you, it involved cleaning the wet tank.

Over six months we found impacted and had to replace three check valves, three solenoid s, two regulators and two ride height valves (maybe unrelated to the material that i characterize as clay desiccant). "Clay" had coated the check valves such that could not clean them. Particles got into solenoid, other valves and cylinders. Over this time I would check the exhausting of the tanks and at times see clay dust blow out. In time that stopped. Hope this helps emphasize this for someone, save you a problem.

Mike

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #3 – April 10, 2013, 12:22:53 am

Quote from: Michael & Jackie – April 09, 2013, 10:39:28 pm

Barry, I wrote some time ago about the white powder (clay I think) and warned...change the desiccant filter regularly, watch this system for its failure causes list of misery.

To review: the prior owner did not change timely is my interpretation. In any case, leveling was not maintained and raise function on front had some problems as well. You could see white material vent when I would test the drain on the four tanks. I got Haldex to suggest solutions, which I reported...so if this new to you, it involved cleaning the wet tank.

Over six months we found impacted and had to replace three check valves, three solenoid s, two regulators and two ride height valves (maybe unrelated to the material that i characterize as clay desiccant). "Clay" had coated the check valves such that could not clean them. Particles got into solenoid, other valves and cylinders. Over this time I would check the exhausting of the tanks and at times see clay dust blow out. In time that stopped. Hope this helps emphasize this for someone, save you a problem.

Mike

After I got home I found my D/S front air bag would not raise when I hit the front raise button or the coach raise. Trying to figure out how to get it raised so I can get underneath to check it out. I can hear the solenoid clicking when I hit the front raise button but it is not letting air into the bag. So it has to be in the manifold. I can't get out of my driveway without raising the coach all the way without ripping out the radiator. Got to leave Thursday AM.
Here it starts piece by piece. How did they suggest you clean the wet tank? I would think that the front 2 tanks would need it also as the powder has progressed throughout the system infecting all the check valves etc.

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #4 – April 10, 2013, 01:12:35 am

Barry, wish I knew how to find my prior post but recall Haldex was very particular about what to not use. I reported Haldex instructions to MOT and they disconnected the wet tank and washed it out with soapy water, no solvents besides water as I recall. Haldex was very understanding, anxious to help, said it not a unique inquiry.

Isaac did the work, ran air to dry, reconnected system and said it helped a lot but as you said clay still throughout the system. We operated a few weeks, put in new filter, ran a while again and found more clay dust, so changed again.

I then came to realize that air was moving incorrectly between the front tanks so Isaac worked there and found all three check valves coated such that could not really even scrape the material off easily. After those replaced, and those solenoids and regulators along the way, they got the system to working as it should.

Later Keith Risch drove, was not pleased and found two ride height valves not working properly. I do not know if those related to the clay.

I was quite frustrated and perhaps impatient with the clay but they worked on it until got it right. It took several months and efforts. I just should have been as concerned about the prior maintenance on this system as of the liquids and those filters. I would liked to have avoided this lesson!

Mike

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #5 – April 10, 2013, 10:59:21 am

In reply to pm, may be of interest....Haldex may have thought it good to remove the connection to the other tanks and wash and dry them but they left it at the wet tank to clean so that is what MOT did.

As for the lines, the general dealer manager suggested removing those but service folks said no.

Separately to add in case you wonder, the clay dust continued to circulate and build in the filter so we replaced the filter after a thousand miles as we worked thru this over months.

Don Hay told me that he had heard of almost a slurry coming from the wet tank when you open the drain valve. Perhaps he can clarify if i reported him wrongly. I did not see that, only air and powder blew out. But perhaps at one time I had that? The coating on the check valves was so tight you could barely even scrape some off. I did see clay dust out a front air tank drain valve.

Hope this clarifies. Mike

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #6 – April 10, 2013, 01:32:06 pm

Quote from: Michael & Jackie – April 10, 2013, 10:59:21 am

Separately to add in case you wonder, the clay dust continued to circulate and build in the filter so we replaced the filter after a thousand miles as we worked thru this over months.

Colton Truck service manager & I checked the air dryer which has 8500 miles on it ( 1 year) and it looked new.

Quote

Don Hay told me that he had heard of almost a slurry coming from the wet tank when you open the drain valve. Perhaps he can clarify if i reported him wrongly. I did not see that, only air and powder blew out. But perhaps at one time I had that?

I did not hear that either. I saw powder blow out of front tank, and the line to the accumulator when I blew air thru it tracing the air lines to correct my air diagram.

Quote

The coating on the check valves was so tight you could barely even scrape some off. I did see clay dust out a front air tank drain valve.
Mike

That is what I am seeing also. see photo.
I tried again to get the raise to work and this AM and it did. I am going to pick up a pair of Bottle Jacks in case I run into this again. If I cant raise it I cant get underneath to work on it

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #7 – April 10, 2013, 07:37:05 pm

Quote

To quote Mike H.: "Don Hay told me that he had heard of almost a slurry coming from the wet tank when you open the drain valve. Perhaps he can clarify if i reported him wrongly. I did not see that, only air and powder blew out. But perhaps at one time I had that? "

Slight correction: It wasn't that I "heard". It happened to me! Within a couple weeks of buying my coach (May, '03), I read that I should check the wet tank frequently, so I did: I wasn't prepared for a greyish fluid the viscosity of honey (but not sticky) to pour into the palm of my hand. I brought it to the attention of the FOT Service Manager (Brad Laidler), who just about lost it (they had just signed off on a 6 month, 6,000 miles bumper-to-bumper warranty). They fixed it promptly. At the time I didn't realize that it was liquified Drierite. I would probably have had a cow had I understood the significance..

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #8 – April 10, 2013, 07:47:39 pm

What causes failure of the desiccant in the dryer ? Does the dissacant get so saturated that it expands and burst the inside of the canister ? Or is the filter faulty to begin with ?
Gary B

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #9 – April 10, 2013, 11:33:06 pm

Quote from: Michael & Jackie – April 10, 2013, 10:59:21 am

Separately to add in case you wonder, the clay dust continued to circulate and build in the filter so we replaced the filter after a thousand miles as we worked thru this over months.
Hope this clarifies. Mike

Was it the air dryer filter that was replaced or is there a filter within the air system?

Air does not circulate through the air dryer. Fresh air comes in from outside, through coach air filter, through turbo, into intake manifold, to air compressor, then to air dryer. Air is always being expended through leaks, ride height & level lowering coach, and brakes.

But it looks like the white dust hangs around a long time, causing a mess on its way back to the atmosphere.

It looks like we will be letting a little air out from our wet tank on a regular basis, like checking oil level and coolant level. Also a quick drain on the two front brake tanks, but less often.

At the very first sign of white powder from air tanks, air dryer filters will be replaced, in addition to changing it about every two years. Would be nice to catch this problem as it just starts. We have changed the two air dryer filters ourselves before. It goes quite fast after dumping all air pressure from system. We don't change the brass pressure release valve on the bottom very often.

Glad you got your coach to raise today Barry.

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #10 – April 11, 2013, 12:01:11 am

Quote from: Barry & Cindy – April 10, 2013, 11:33:06 pm

But it looks like the white dust hangs around a long time, causing a mess on its way back to the atmosphere.

It looks like we will be letting a little air out from our wet tank on a regular basis, like checking oil level and coolant level. Also a quick drain on the two front brake tanks, but less often.

Glad you got your coach to raise today Barry.

Looks like I will be able to leave tomorrow as I got the coach raised. I found that white dust on the solenoids also. I have some spares that I use as I take some out to change the "O" rings. I am putting the solenoids in white vinegar and it looks like the powder is being dissolved. I will use them again to replace existing ones to clean them.

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #11 – April 11, 2013, 01:05:05 am

I'm confused .I though all the compressed air for the air brakes and leveling system passed through the dryer on it's way to the wet tank?Gam

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #12 – April 11, 2013, 07:56:52 am

Gam,

You're right. I don't think Barry is being conservative enough. I change my drier according to FT's recommended schedule, which is every 18 months. If I ever saw moisture in the wet tank, I'd change the drier immediately.

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #13 – April 11, 2013, 11:28:02 pm

Quote from: gam – April 11, 2013, 01:05:05 am

I'm confused .I though all the compressed air for the air brakes and leveling system passed through the dryer on it's way to the wet tank?Gam

You are correct, output of compressor is the air dryer, then dry air goes to wet tank. Both brake tanks get their air from the wet tank. All air brakes & accessories, like leveling, etc get their air from brake tanks.

When it was said air does not circulate through air dryer, it meant that air from all tanks does not circulate back to air dryer. Only new fresh air enters air dryer, so air contaminated with clay dust in the system does not continue to contaminate a new air dryer filter. So there would be no reason to change air dryer filters more often after changing them because of finding clay dust in the tanks.

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #14 – April 12, 2013, 12:35:45 am

But the air dryers job isn't to filter the air. The air supply for this system comes from the engine intake manifold . The dryer does have a small filter that is to remove any contaminants picked up after the main engine filter.The job of the air dryer is to remove water and oil vapor from the system. The reason to change the canister is to replace the desiccant. Most times silica gel is used for adsorption ,but some types of clay can be used.I'm thinking this clay dust is the desiccant from a canister that was damaged or in service to long.Gam

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #15 – April 12, 2013, 01:02:39 am

Quote from: gam – April 12, 2013, 12:35:45 am

The job of the air dryer is to remove water and oil vapor from the system. The reason to change the canister is to replace the desiccant. Most times silica gel is used for adsorption ,but some types of clay can be used. I'm thinking this clay dust is the desiccant from a canister that was damaged or in service to long.Gam

In my case that is what happened.
I waited to long to replace it. Since I did not see moisture at the petcock I mistakenly thought it did not need to be changed at that interval. Expensive lesson in time and $$$

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #16 – April 12, 2013, 09:14:40 am

Where can you get just the Oil rings for the 6 pack Air Solenoid Valve ?

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #17 – April 12, 2013, 09:24:47 am

Crazy J,

From HWH. Part number RAP 6554 (6 large O-rings and 6 small O-rings). $8 per package.

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #18 – April 12, 2013, 09:41:03 am

Quote from: Crazy J – April 12, 2013, 09:14:40 am

Where can you get just the Oil rings for the 6 pack Air Solenoid Valve ?

Grainger or Ace Hardware carries them also.
They are both 1/16 wall O rings, # 15 (.691OD) and # 28 (1.504OD)
HWH Leveling Valve

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #19 – April 12, 2013, 10:14:02 pm

You can also disassemble the valve and there is another o ring inside the valve. I went to a hydraulic shop with all 3 o rings and they had a guage to check the sizes and I got enough to do 2 6 packs for about $7.00. It was a little tricky to get the valve apart, but by using 2 of the nuts that hold on the coils and locking them together was able to disassemble. After I did that the coach no longer leaked down.

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #20 – April 14, 2013, 09:39:11 am

Thanks Rudy, Barry & Red Tractor.

For the information on the O-Rings.

Air System Dust, Wet Tank Cleaning

Reply #21 – December 19, 2013, 10:37:13 pm

Quote from: Michael & Jackie – April 10, 2013, 01:12:35 am

Barry, wish I knew how to find my prior post but recall Haldex was very particular about what to not use. I reported Haldex instructions to MOT and they disconnected the wet tank and washed it out with soapy water, no solvents besides water as I recall. Haldex was very understanding, anxious to help, said it not a unique inquiry.

Isaac did the work, ran air to dry, reconnected system and said it helped a lot but as you said clay still throughout the system. We operated a few weeks, put in new filter, ran a while again and found more clay dust, so changed again.

Mike

You will find several threads in the past where I wrote of desiccant dust from the Haldex getting into the air brake and level system and causing havoc. I reported everything from coated check valves to contaminated solenoids and means to address, plus the symptoms of such problems, mostly related to leveling and ride height control.

In recent months we thought the problem resolved and then I had a Travel mode lean problem with the engine off after installing air bags. I also reported dust had actually come to accumulate in the air bags and might puff out when making a rapid change from Raise.

The latest: I hope this is the final solution. I am sure you check the wet tank drain valve often for dust but I have had people ask me what that was about and where it was, so I know some may not know of it. I was told some dust would be normal. So its frequent appearance was not a great alarm.

In the latest, Keith Risch became puzzled about an aspect of this leaning and still frequent dust and decided to remove the wet tank. Over a year ago we had washed it per Haldex process. This time Keith and Mike applied external air pressure to the removed tank and covered the shop up with dust....they had to run to close coach doors. Fine dust was blown out. They learned that large deposits had continued in that tank regardless of the work done before. The small puffs when I would open the valve only showed the larger problem, it did not really drain the dust.

The solution? They worked the tank with CLR and did inspections after that cleaning. They are convinced this now removed all the dust, lots of it, and then went to work on air lines. So if you have a problem with the dust after you think all was clean, consider a new tank or this possible option to clean the tank. I think it rare you will need this, but if it happens, this information may be helpful.

Mike

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #22 – December 20, 2013, 08:42:49 am

Michael: Considering all the time and expense involved in cleaning this dust out of a contaminated air system, I wonder if it would not be more economical to just go directly to tank replacement? Especially in the case of the wet tank, which probably contains the greatest percentage of "wandering" clay dust. Those tanks are not that big - I would think it would be pretty easy to locate a suitable off-the-shelf replacement. Even if it had to be custom fabricated, seems it would be cost/time effective to start the decontamination process with a brand new, CLEAN, wet tank.

Just the idle musings of a "armchair quarterback", who hopes to never have to deal with this problem.

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #23 – December 20, 2013, 09:44:25 am

Would it be feasible and logical to install an additional appropriate filter after the dryer? THANKS JC

Re: Air Dryer desiccant contamination creates symptoms of air leak (split from Re: AIR LEAK)

Reply #24 – December 20, 2013, 09:49:39 am

Oh for sure chuck! Yes! Just should have been done a year ago. No one thought of a new one as the tank was washed out a year ago and thought that removed from the equation.

We have learned to not overlook this option of that tank remaining the cause of air leaks or mismanagement. I was seeing a periodic and continuing supply of dust even after the tank was rinsed a year ago.

One may have identified and solved a dust problem without having to do this. For a long time each fix of a solenoid or valve etc was thought to be the last for us, that the dust had worked its way out of the system. It had not, a huge supply remained. Try the tank clr clean or a new tank if dust continues.

Thanks,
Mike

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